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Level crossing
A level crossing (a primarily British term; usually known as a railroad crossing in the United States) is an intersection where a railway line crosses a road or path at the same level, as opposed to the railway line crossing over or under using a bridge or tunnel. The term also applies when a light rail line with separate right-of-way or reserved track crosses a road in the same fashion. Other names include railway crossing, grade crossing, road through railroad, railroad crossing and train crossing. Overview Early level crossings had a flagman in a nearby booth who would, on the approach of a train, wave a red flag or lantern to stop all traffic and clear the tracks. Manual or electrical closable gates that barricaded the roadway were later introduced. The gates were intended to be a complete barrier against intrusion of any road traffic onto the railway. In the early days of the railways much road traffic was horsedrawn or included livestock. It was thus necessary to provide a real barrier. Thus, crossing gates, when closed to road traffic, crossed the entire width of the road. When opened to allow road users to cross the line, the gates were swung across the width of the railway, preventing any pedestrians or animals getting onto the line. The first U.S. patent for such crossing gates was awarded on 27 August 1867, to J. Nason and J. F. Wilson, both of Boston. With the appearance of motor vehicles, this barrier became less effective and the need for a barrier to livestock diminished dramatically. Many countries therefore replaced the gated crossings with weaker but more highly visible barriers and relied upon road users following the associated warning signals to stop. At railway stations, a pedestrian level crossing is sometimes provided to allow passengers to reach other platforms in the absence of an underpass or bridge. Where third rail systems have level crossings, there is a gap in the third rail over the level crossing, but the power supply is not interrupted since trains have current collectors on multiple cars. Safety Level crossings constitute a significant safety concern internationally. On average, each year 400 people are killed in the European Union and over 300 in the United States in level crossing accidents. Collisions can occur with vehicles as well as pedestrians; pedestrian collisions are more likely to result in a fatality. Among pedestrians, young people (5–19 years), older people (60 years and over) and males are considered to be high risk users. In terms of warning systems, level crossings are either passive crossings which have warnings such as signs, or active crossings which have automatic warning devices such as boom gates, flashing lights and warning tones. Fewer collisions take place at level crossings with active warning systems. Today radar sensor systems for automatic level crossing free detection are a cheap way to improve safety of level crossings. Major accident Level crossings present a significant risk of collisions between trains and road vehicles. This list is not a definitive list of the world's worst accidents and the events listed are limited to those where a separate article describes the event in question. Crossings around the world Asia Malaysia All crossings in Malaysia are still largely manually operated, where the barriers are lowered using a manual switch when trains approach. A significant number of crossings are without barriers. Railway electrification in Malaysia has gradually eliminated level crossings in Peninsular Malaysia, replacing those along nearly all upgraded lines with large overhead viaducts or deep underground tunnels, and simply cutting off non-essential crossings outright. But there are still some that are used on the line between Port Klang - Westport (Pulau Indah). However, it seems like only the level crossing near Port Klang Komuter Station has the barrier. Singapore Most of Singapore's railway network is either underground or on elevated viaducts, meaning that level crossings are rare. Europe Belgium At a level crossing, any overhead electric power cables must also cross. This led to a conflict where a mainline railway that crossed one of the country's once extensive interurban tram lines (vicinal or buurtspoorweg) was electrified. In at least one location, this led to the tram overhead being dismantled. Automatic level crossings in Belgium have two red lights, a "moon-white" light and (usually) barriers. The white light flashes for half a second at regular intervals to inform drivers and pedestrians that they can cross the level crossing, and that the signal is in working order. In some cases the white light is absent; the Belgian traffic law of 1975 does not cover that situation. Britain Britain's first automatically operated level crossing came into operation at Spath near Uttoxeter in Staffordshire in May 1961. There were 8,200 level crossings in the UK in 2005, of which 1,600 were road crossings. This number is gradually being reduced as the risk of accident at level crossings is considered high. The director of the UK Railway Inspectorate commented in 2004 that "the use of level crossings contributes the greatest potential for catastrophic risk on the railways." Bridges and tunnels are now favoured, and there is a commitment on the part of UK rail authorities not to build new level crossings, and to reduce the number of existing level crossings. The cost of making significant reductions, other than by simply closing the crossings, is substantial; some commentators argue that the money could be better spent. Some 6500 crossings were user-worked crossings or footpaths with very low usage. The removal of crossings can also improve train performance as some crossings have low rail speed limits enforced on them to protect road users. In fact, between 1845 and 1933, there was a speed limit on level crossings of turnpike roads adjacent to stations for lines whose authorising Act of Parliament had been consolidated in the, although this limit was at least sometimes (and possibly often) disregarded. In the United Kingdom, major crossings were normally situated within easy sight of a signal box, and usually directly adjacent to the signal box, to ensure that the signalman could verify that the road was clear before allowing a train onto the crossing. The traditional form of road crossing on British railways from the mid-19th century consisted of four wooden gates (two on each side of the railway). These prevented road traffic from crossing when closed, and when open lay across the railway to prevent horses and livestock inadvertently escaping from the road to the railway. Many gated crossings have been replaced by lifting barriers, which are easier to mechanise. "Full barriers" consist of barriers each side of the track which block the full width of the road, and "half barriers" consist of a single arm each side of the road, which block only oncoming traffic. Half barriers were considered to have an advantage as motorists are less likely to be stranded on the crossing and unable to exit, but cases where impatient motorists have driven around the barriers have raised safety concerns. Video cameras are now often used at crossings to allow the human operator to be some distance from the crossing. On lightly-used railways many crossings are sited next to station stops or other stopping points, and are crew operated. The guard pushes a plunger to operate the crossing. On completion of the crossing sequence, an indicator light permits the train to proceed if the crossing is observed by the train driver to be clear. After the train has cleared the crossing, it re-opens to road traffic. In Ireland, instead of an open crossing there may be manually-operated gates, which the motorist must open and close. These have significant risks, as they are unsafe to use without a knowledge of the train timetable; motorists may be instructed to telephone the railway signaller, but may not always do so. To ensure that the barriers are noticed and to draw attention, public road crossings are fitted with flashing lights plus a warning bell, siren or a voice sounder to warn pedestrians that a train is approaching. Some crossings also have telephones which connect to the relevant signal box, so that in case of an emergency, or a large slow moving vehicle wanting to use the crossing, the signalman's attention can be drawn promptly to the hazard and action can be taken. Some "automatic open crossings", with warning lights and bells but no barriers, have been introduced, but their expansion was largely halted after the Lockington rail crash. Some smaller crossings, particularly pedestrian crossings on low-speed lines, have only a warning sign and raised pathway across the track itself. In November 2004, there were two major accidents on UK level crossings: one involved a car driver committing suicide, who caused the death of seven people (Ufton Nervet rail crash); another involved a train carrying 50 school children; this resulted in no fatalities but a number of injuries. These incidents have increased efforts to review the placing of level crossings and to eliminate them where this is practicable. In the UK it has also been suggested that cameras similar to the type used to detect drivers who run traffic lights be deployed at level crossings, and that penalties for ignoring signals should be much more severe. UK has few level crossing types: Full list of types: AOCL - Automatic Open Crossing Locally Monitored AHB - Automatic Half Barrier ABCL - Automatic Barrier Crossing Locally Monitored MCB - Manually Controlled Barriers MCG - Manually Controlled Gates UWC - User Worked Crossing TMO - Trainman Operated Crossing MWL - Miniature Warning Lights AOCL functions like normal ungated crossing, amber lights turn on for 3 seconds, light turns off and red lights start to flash, white flashing light indicating that the crossing is working on the track side is activated. ABCL functions like AOCL but with barriers. AHB functions like North American crossings do, amber light turns on for 3 seconds, light turns off, red lights start to flash, barrier lowers. The crossing operation is superivsed by a signaller who has indications. MCB known as full barrier crossing functions like this, amber lights turn on for 3 seconds, light turns off, red lights start to flash, left barrier lowers, after left barrier fully lowered, right barrier lowers, when all barriers are lowered the alarm stops. MCG are known as old manually operated gates. They are operated either by signaller, crossing keeper or traincrew, by wheel, by hand or by motor. UWC are user operated level crossings, they may have phones that the user needs to use before crossing the railway, others may not have phones and users have to look both ways, the crossings normally have gates shut and the gates open opposite the railway so if the gates are left open it will not foul the railway, sometimes they have barriers operated by a pump or motor. TMO known as traincrew operated crossings are operated by traincrew, those crossings normally have gates shut across the railway like MCG does, sometimes those crossings have barriers. The crossing is marked by a stop board instructing to open crossing gates or operate barriers. MWL are known as miniature stop lights are red and green lights automatically operated by passage of trains, those lights may be at UWC or footpath crossings. British Transport Police typically prosecute motorists who jump the barriers, for either trespass or failing to conform with a traffic signal. A particular problem has been that the responsibility for road safety at crossings is entirely outside the control of the railways. In 2006 there were legal proposals to permit Network Rail to be involved in the road side safety of crossings. This would allow the introduction of anti-slip surfaces and also barriers to prevent motorists driving around crossing arms and, it is hoped, reduce the number of crossing-related deaths. Network Rail is pursuing a policy of closing level crossings at the rate of over 100 a year in the interests of safety, and replacing them with road bridges or footbridges. The number of level crossings on rail lines controlled by Network Rail went from 7,937 in 2003-04 to 6,322 on 19 January 2014. Pedestrian crossings The use of pedestrian crossings at stations is now rare in the UK, although in the past it was common for passengers to walk across the line between platforms. It is still common in many other countries, and on lines with less traffic. At Settle, for example, before the footbridge was installed in the 1990s, while passengers from Leeds walked across the line the driver's kettle was topped up with hot water. With a few exceptions, such as at Carmarthen, the remaining such crossings are on heritage railways or are used to let passengers who cannot climb stairs to the footbridge move between platforms. For the episode of British motoring television programme Top Gear on 25 February 2007, Network Rail staged an incident in which a locomotive was driven into a Renault Espace at around to graphically illustrate the dangers of "running the risk" (see British Rail Class 31 in the media). "Modular" level crossing barriers were considered by Network Rail when they introduced a new modular building system in 2008. Being modular, they can be assembled and installed in just a few hours. North America Canada Grade crossing protection practices in Canada are virtually identical to those in the United States (see below) using the same alternating flashing red lights and gate arms. The only significant differences are the crossbuck signs, which have no wording but are white with a red outline, and the advance-warning sign, which is a yellow diamond shape with a diagram of a track crossing a straight segment of road (similar to a crossroads sign, except that the horizontal road is replaced by a track). Before changes in regulations mandated bilingual (English and French) or no-wording signs, crossbucks were nearly identical to those in the States, except that they read "Railway Crossing" instead of "Railroad Crossing." The red lights also flash a little faster than in the United States. United States Crossing identification Every crossing, whether above grade, below grade, or at grade, is required to be assigned a unique identifier which is a six-digit number and a trailing letter used as a checksum. This identifier is called a Grade Crossing Number, and is usually posted with a sign or sticker on the sign or equipment. This allows a particular crossing anywhere in the United States to be precisely identified as to its exact location in the event of an incident involving that crossing. Traffic control devices All public crossings in the United States are required to be marked by at least a crossbuck. The 2009 Manual on Uniform Traffic Control Devices requires passive crossings (crossings without actuated flashing lights or gates) to have either stop signs or yield signs in addition to the crossbuck, unless a flagger will stop traffic every time a train approaches. Normally a yield sign is used, unless it is determined that all vehicles should stop at the crossing, such as a location with poor sight distance. All passive crossings must be upgraded to meet this standard by December 31, 2019. If the crossing has more than one railroad track, the crossbuck is required to have a small sign beneath it denoting the number of tracks. As traffic on the road crossing or the rail crossing increases, safety features are increased accordingly. More heavily trafficked crossings have automatic warning devices (AWDs), with alternately flashing red lights to warn automobile drivers and a bell to warn pedestrians. Additional safety is attained through crossing gates that block automobiles' approach to the tracks when activated. Increasingly, crossings are being fitted with four-quadrant gates to prevent circumventing the gates. Operation of a typical AWD-equipped railroad crossing in the United States is as follows: * About 30 seconds before arriving at the crossing, the train trips a track circuit near the crossing, triggering the crossing signals. The lights begin to flash alternately, and a bell (or bells) mounted at the crossing begins ringing. After several seconds of flashing lights and ringing bells, the crossing gates (if equipped) begin to lower, which usually takes 5–10 seconds. Some AWDs silence the bell once the gates are fully lowered (typically seen on most Norfolk Southern and CSX crossings); most continue ringing the bells throughout (Union Pacific, BNSF Railway). The lights continue to flash throughout regardless. *About 15–20 seconds before arriving at the crossing, the train begins ringing its bell and sounding its horn in accordance with NORAC rule 14L or GCOR rule 5.8.2(7): two longs, one short, and one long. These are prolonged or repeated until the engine occupies the crossing. If the AWD is equipped with a horn in accordance with FRA Quiet Zone rules, the AWD may provide the whistle signal instead of the train; however, the train is required to ring its bell regardless. *After the train has cleared the crossing, the bells (if silenced) may begin ringing again (such as the Florida East Coast Railway), and the gates (if equipped) begin to rise. Once the gates have completely risen back to their fully raised position, all warning signals, including the lights and bells, are deactivated. Some AWD track circuits are equipped with motion detectors that deactivate the crossing signal if the train stops or slows significantly before arriving at the crossing. As indicated above, the pattern of the bells at each individual crossing can be different. (These bells should not be confused with the bells that are mounted on the trains.) Generally, the bells follow one of these patterns: *The bell begins ringing when the lights begin flashing and stops when the gates have completely lowered. *The bell begins ringing when the lights begin flashing and stops when the gates begin to go up following the passing of the train. *The bell begins ringing when the lights begin flashing and stops when the gates have completely lowered, and then resumes ringing when the gates begin to go up, until the gates have returned to their original position. *The final, and most common, practice is for the bells to begin ringing when the lights begin flashing and continue until the gates have gone up after the train passes. Some level crossings that are located too close to intersections with traffic lights program the signals so when the approaching train trips the track circuit, it not only activates the crossing signals, but also changes the traffic lights facing the crossing to green, to clear any traffic that may be queued on the crossing. Some track circuits place the signals into flash mode the entire time the AWDs are active. In cases where railroads share the right of way with vehicular traffic, simple railroad preemption may cause an all-red flash in traffic lights. A few level crossings still use wigwag signals, which were developed in the early 1900s by the Pacific Electric Railway interurban system in the Los Angeles region to protect its many level crossings. Though now considered to be antique, around 100 such signals are still in use, almost all on branch lines. By law, these signals must be replaced by the now-standard alternating red lights when they are retired. US Federal Railroad Administration regulations restrict trains to a maximum speed of at standard grade crossings. Crossings are permitted up to only if an "impenetrable barrier" is in place to block traffic when a train approaches. Crossings are prohibited at speeds in excess of . A track that will run high-speed trains in excess of is being tested in Illinois between Chicago and St. Louis, Missouri. Here, due to the high speed of the trains, gates that totally prevent road traffic from reaching the tracks are mandatory on all level crossings. Steel mesh nets were tested on some crossings to further prevent collisions, but these were removed because of maintenance issues in 2001. A new device called "StopGate" has been installed at four locations, one in Madison, Wisconsin; another in Monroe, Wisconsin and two in Santa Clara, California (on a light rail system). This system resembles a fortified version of a standard crossing gate, with two larger arms blocking the entire width of the roadway and locking into a securing device on the side of the road opposite the gate pivot mechanism. The gate arms are reinforced with high-strength steel cable, which helps the gate absorb the impact of a vehicle attempting to crash through the gate. The manufacturer claims that the StopGate can stop a truck within . Already the system has been tested at the Madison crossing, when the system stopped a truck while a Wisconsin and Southern Railroad train was in the crossing. Another new type of barrier is being tested in Michigan that is hoped will reduce the number of times drivers attempt to drive around lowered crossing gates. The new devices are called "delineators" consisting of a series of flexible bollards that raise vertically out of vertical tubes in the pavement when the crossing signal is activated. The delineators are designed so that they will not be broken and will not damage vehicles if they are hit, allowing vehicles to exit the level crossing if they are already within it when the gates are activated. The test period for the new barrier began on 5 December 2007, and will run for a period of 17 months. Locomotive equipment In the United States and in countries following United States practices, a locomotive must have a bright headlight and ditch lights (two lights located below the headlight), a working bell, and a whistle or horn that must be sounded four times (long-long-short-long), similar to the signal for the International Morse Code letter "Q", as the train approaches the crossing. Some American cities, in the interest of noise abatement, have passed laws prohibiting the sounding of bells and whistles; however, their ability to enforce such rules is debatable. In December 2003 the US Federal Railroad Administration published regulations that would create areas where train horns could be silenced, provided that certain safety measures were put in place, such as concrete barriers preventing drivers from circumventing the gates or automatic whistles (also called Wayside horns) mounted at the crossing (which reduce noise pollution to nearby neighborhoods). Implementation of the new "Quiet Zone" Final Rule was delayed repeatedly but was finally implemented in the summer of 2005. Rail "Quiet Zone" crossings still require bells as part of the (AWDs) in addition to the wayside horns. The wayside horns usually are sets of speakers that are directed at the crossing mounted right up on a pole. These audible devices are not similar to a train horn. Oceania Australia Australian railways generally follow United States practices, and they have increasingly been employing American-made crossing warning equipment, such as level crossing predictors, which are able to provide a consistent amount of warning time for trains of widely varying speeds. There are many different types of rail crossings in Australia, as the railways that run through rural areas often do not have barriers or even lights/bells to warn of incoming trains, urban crossings will either have lights and bells or lights, bells, and boomgates In Melbourne, there are several level crossings where electrified train tracks cross roads with electrified tram tracks. These crossings are fitted with equipment to change the voltage supplied to the overhead wiring depending on the vehicle using the crossing at that point in time. Trains are severely speed-limited across these intersections. Although all cases where a train line crosses a road are level crossings whether or not they are signed, a tram track in its own right of way crossing a road can also be a level crossing if it is signed with a crossbuck reads either "TRAM WAY CROSSING" or "RAIL WAY CROSSING". Otherwise, it is a regular intersection and usually has either traffic lights or a give way sign facing the road (see Gallery). Some recent innovations in Australia are to provide crossbucks with a pair of flashing yellow lights at about 200m before the level crossing, particularly where there are curves and visibility problems on the road, called Advance Active Warning Signals (AAWS). These are used where road speeds are high, and braking distances are extended, and/or where the level crossing is obscured by blind curves and/or sunlight. Another innovation is to transmit level crossing warning signals by radio into the cabin of nearby vehicles. This would be particularly useful at passive crossings, not yet fitted with flashing lights. Unusual crossings Bishton level crossing in Wales is unusual in that it is partly replaced by an underpass for low clearance cars, leaving the level crossing for high clearance trucks. There are many similar crossings on the line between London and (built by the Great Eastern Railway Company), including at and Great Chesterford, and also near Cambridge Science Park on the former Cambridge & St. Ives Branch (this is now used only by pedestrians and cyclists). The level crossing at in Essex also has this arrangement. Runway crossings Australia * Kingsford Smith Airport had a runway crossing, when that runway was extended. The railway was later deviated with sharp curves to avoid that runway. * , while not having an actual runway crossing, had extra low signals and telegraph wires at the railway station to improve safety for low flying aircraft landing or taking off. Northern Ireland * There was a runway crossing on the Belfast–Derry railway line. The runway was interlocked with conventional railway block instruments to the control tower. See also *At-grade intersection *Automatic full barriers *Billups Neon Crossing Signal *Boom barrier *Crossbuck *Four-quadrant gate *Grade separation *Category:Level crossing accidents *Whistle post *Lists of rail accidents :*List of train accidents by death toll *List of road accidents *Wigwag *Winston Churchill Avenue, a street crossing an airport runway References Bibliography * External links Category:Traffic signs Category:Level crossings Category:Rail junction types Category:Road infrastructure Category:Road hazards